JP2005171791A - Variable valve system of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce nonuniformity of the temperature generated in the longitudinal direction of a control shaft for changing a lifting/ operating angle in a lifting/operating angle variable mechanism. <P>SOLUTION: An actuator 13 is installed on one end of the control shaft 12 in the lifting/operating angle variable mechanism 1 capable of continuously, expansively and contractively controlling a lifting/operating angle of an intake valve by rotating the control shaft. Lubricating oil is supplied to a plurality of bearing means 29 for rotatably supporting the control shaft. The lubricating oil is supplied to a hollow part inside of the control shaft 12 extending in the longitudinal direction of the control shaft 12 via a one end side bearing means 29e for supporting one end side of the control shaft among the plurality of bearing means 29. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a variable valve mechanism for an internal combustion engine.

Patent Document 1 includes a lift / operating angle variable mechanism capable of simultaneously and continuously expanding and reducing the lift / operating angle of the intake valve, and reducing the pumping loss by simultaneously changing the lift and operating angle of the intake valve. An intake control device for an internal combustion engine that realizes control of an intake air amount that is sufficiently reduced and does not depend on a throttle valve is disclosed.
JP, 2002-256905, A In Japanese Patent Application Laid-Open No. 2002-256905, when the intake valve lift amount between the cylinders varies due to various reasons such as dimensional tolerance of parts, assembly of parts, etc. The amount of intake air supplied in between varies, and as a result, the generated torque of the internal combustion engine varies. In such a state, unpleasant vibrations and noises are generated in the internal combustion engine, and the idle quality that is particularly required to be stable and quiet is greatly adversely affected. The variation in the lift amount of the intake valve is about several μm to several hundred μm, and has hardly been a problem in an internal combustion engine that controls the intake amount with a conventional fixed cam and throttle valve.

  Therefore, in the intake control device as disclosed in Patent Document 1, the variation in the lift amount between the cylinders falls within a predetermined range.

  However, in this patent document 1, since the intake air amount control independent of the throttle valve is realized, the valve lift amount also takes a very small value in an extremely low load region such as an idle, and immediately after starting. There may be a problem in idle quality until the air is sufficiently warmed.

  This is the case where the inventor of the present application measured the temperature distribution in the longitudinal direction of the control shaft of the lift / working angle variable mechanism in the lift / working angle variable mechanism, taking the in-line cylinder arrangement as an example. This is because it has been clarified that temperature nonuniformity occurs in the control shaft.

  In other words, the control shaft that continuously expands and reduces the lift / operating angle of the intake valve by rotating itself causes non-uniform thermal expansion in the same direction due to non-uniform temperature distribution in the longitudinal direction. As a result, there is a possibility that the torque generated by the internal combustion engine may vary due to variations in the lift amount of the intake valve between the cylinders.

  Therefore, the main problem of the present invention is that in the variable valve mechanism of the internal combustion engine provided with the variable lift / operating angle mechanism capable of continuously expanding and reducing the lift / operating angle of the intake valve, The object is to reduce temperature non-uniformity that occurs in the longitudinal direction of the control shaft that changes the lift and operating angle of the intake valve.

  Therefore, the present invention provides a lift / working angle variable mechanism capable of continuously expanding and reducing the lift / working angle of the intake valve by rotating the control shaft, an actuator attached to one end of the control shaft, A plurality of bearing means for rotatably supporting the shaft, the lubricating oil is supplied to the plurality of bearing means, and the internal combustion engine is operated by changing the lift and operating angle of the intake valve according to the engine operating state In a variable valve mechanism of an internal combustion engine capable of controlling an intake air amount to an engine, one end side of a plurality of bearing means that supports one end side of a control shaft in a hollow portion extending along the longitudinal direction of the control shaft The lubricating oil is supplied through the bearing means. As a result, lubricating oil having a relatively high temperature (a large amount of supplied heat) is supplied to one end side of the control shaft to which the actuator having a large heat capacity is attached. Therefore, the temperature of the control shaft in the longitudinal direction of the control shaft Unevenness can be reduced.

  According to the present invention, it is possible to reduce the temperature non-uniformity of the control shaft in the longitudinal direction of the control shaft, so that a non-uniform temperature distribution occurs in the longitudinal direction of the control shaft, thereby causing non-uniform thermal expansion in the same direction. It is possible to reduce the occurrence. Therefore, variation in the lift amount of the intake valve between the cylinders is reduced, and occurrence of variation in the torque generated by the internal combustion engine can be suppressed.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall configuration diagram of the system of the present invention, and FIG. 2 is an explanatory diagram showing a schematic configuration of a variable valve mechanism. FIG. 1 shows a case where the present invention is applied to an in-line four-cylinder internal combustion engine, but the present invention is also applicable to an internal combustion engine having another cylinder arrangement such as a V type and a multi-cylinder internal combustion engine other than four cylinders. Is possible.

  The variable valve mechanism that can continuously change the valve lift characteristics of the intake valve includes a lift / operating angle variable mechanism 1 that changes the lift / operating angle of the intake valve, and a phase of a center angle of the lift (a crank (not shown)). And a phase variable mechanism 21 for advancing or retarding the phase relative to the shaft. In FIG. 1, reference numeral 28 denotes an exhaust side cam for opening and closing the exhaust valve. In the present embodiment, a very general linear motion cam (lift / operating angle and lift center angle are fixed) is used. However, as with the intake side, a variable valve mechanism may be employed.

  First, the lift / operating angle variable mechanism 1 will be described with reference to FIGS. 1 and 2. The lift / operating angle variable mechanism 1 has been previously proposed by the applicant of the present invention. However, since it has been publicly known, for example, in Japanese Patent Application Laid-Open No. 11-107725, only the outline thereof will be described.

  The lift / operating angle variable mechanism 1 includes an intake valve 11 slidably provided on a cylinder head 25, a drive shaft 2 rotatably supported by a cylinder head 25 and a cam bracket 26 on the cylinder head 25, The drive shaft 2 is rotatably supported by a plurality of bearing means 29 including an eccentric cam 3 fixed by press-fitting or the like, and the same cam bracket 26 and cam bracket cap 27 above the drive shaft 2 and driven. A hollow control shaft 12 disposed in parallel with the shaft 2, a rocker arm 6 slidably supported by an eccentric cam portion 18 of the control shaft 12, and a tappet 10 disposed at the upper end of each intake valve 11 And a rocking cam 9 that comes into contact therewith. The eccentric cam 3 and the rocker arm 6 are linked by a link arm 4, and the rocker arm 6 and the swing cam 9 are linked by a link member 8.

  In the present embodiment, there are five bearing means 29, the one that is farthest from a lift / operating angle control actuator 13, which will be described later, is used as a bearing means 29 a, and the bearing means in the order of approaching the lift / operating angle control actuator 13 29b, 29c,... 29e.

  As will be described later, the drive shaft 2 is driven by a crankshaft of the engine via a timing chain or a timing belt.

  The eccentric cam 3 has a circular outer peripheral surface, the center of the outer peripheral surface is offset from the axis of the drive shaft 2 by a predetermined amount, and the annular portion of the link arm 4 is rotatably fitted on the outer peripheral surface. Match.

  The rocker arm 6 is supported by the eccentric cam portion 18 so as to be swingable at the substantially central portion thereof, and the arm portion of the link arm 4 is linked to one end portion thereof via the connecting pin 5 and the other end portion. In addition, the upper end portion of the link member 8 is linked via the connecting pin 7. The eccentric cam portion 18 is eccentric from the axis of the control shaft 12, and accordingly, the rocking center of the rocker arm 6 changes according to the angular position of the control shaft 12.

  The swing cam 9 is fitted to the outer periphery of the drive shaft 2 and is rotatably supported, and the lower end portion of the link member 8 is linked to the end portion extending laterally via the connecting pin 17. . On the lower surface of the swing cam 9, a base circle surface concentric with the drive shaft 2 and a cam surface extending in a predetermined curve from the base circle surface are continuously formed. These base circle surface and cam surface are in contact with the upper surface of the tappet 10 according to the swing position of the swing cam 9.

  That is, the base circle surface is a section where the lift amount becomes 0 as a base circle section, and when the swing cam 9 swings and the cam surface comes into contact with the tappet 10, it gradually lifts. A slight ramp section is provided between the base circle section and the lift section.

  As shown in FIGS. 1 and 2, the control shaft 12 is configured to rotate within a predetermined angle range by a lift / operating angle control actuator 13 provided at one end. The lift / operating angle control actuator 13 includes, for example, a servo motor that drives the control shaft 12 via the worm gear 15, and is controlled by a control signal from the engine control unit 19. The rotation angle of the control shaft 12 is detected by the control shaft sensor 14.

  The operation of the variable lift / operating angle mechanism 1 will be described. When the drive shaft 2 rotates, the link arm 4 moves up and down by the cam action of the eccentric cam 3, and the rocker arm 6 swings accordingly. The swing of the rocker arm 6 is transmitted to the swing cam 9 via the link member 8, and the swing cam 9 swings. The tappet 10 is pressed by the cam action of the swing cam 9, and the intake valve 11 is lifted.

  Here, when the angle of the control shaft 12 changes via the lift / operation angle control actuator 13, the initial position of the rocker arm 6 changes, and consequently, the initial swing position of the swing cam 9 changes.

  For example, if the eccentric cam portion 18 is positioned on the upper side in FIG. 2, the rocker arm 6 is positioned upward as a whole, and the end portion on the connecting pin 17 side of the swing cam 9 is relatively lifted upward. It becomes a state. That is, the initial position of the swing cam 9 is inclined in a direction in which the cam surface is separated from the tappet 10. Therefore, when the swing cam 9 swings as the drive shaft 2 rotates, the base circle surface is kept in contact with the tappet 10 for a long time, and the period during which the cam surface is in contact with the tappet 10 is short. Therefore, the lift amount is reduced as a whole, and the angle range from the opening timing to the closing timing, that is, the operating angle is also reduced.

  On the contrary, if the eccentric cam portion 18 is positioned downward in FIG. 2, the rocker arm 6 is positioned downward as a whole, and the end portion of the swing cam 9 on the side of the connecting pin 17 is pushed downward relatively. It will be in the state. That is, the initial position of the swing cam 9 is inclined in a direction in which the cam surface approaches the tappet 10. Therefore, when the swing cam 9 swings as the drive shaft 2 rotates, the portion that contacts the tappet 10 immediately shifts from the base circle surface to the cam surface. Therefore, the lift amount is increased as a whole, and the operating angle is increased.

  Since the initial position of the eccentric cam portion 18 can be continuously changed, the valve lift characteristic continuously changes accordingly. That is, the lift and the operating angle can be continuously expanded and contracted simultaneously. Depending on the layout of each part, for example, the opening timing and closing timing of the intake valve 11 change substantially symmetrically as the lift and operating angle change.

  Next, as shown in FIG. 2, the phase varying mechanism 21 relatively rotates the sprocket 22 provided at the front end of the drive shaft 2 and the sprocket 22 and the drive shaft 2 within a predetermined angle range. And a phase control actuator 23 to be operated. The sprocket 22 is interlocked with the crankshaft via a timing chain or a timing belt (not shown). The phase control actuator 23 is composed of, for example, a hydraulic or electromagnetic rotary actuator, and is controlled by a control signal from the engine control unit 19. The action of the phase control actuator 23 causes the sprocket 22 and the drive shaft 2 to rotate relative to each other, thereby delaying the lift center angle in the valve lift. That is, the lift characteristic curve itself does not change, and the whole advances or retards. This change can also be obtained continuously. The control state of the phase variable mechanism 21 is detected by the drive shaft sensor 16 that responds to the rotational position of the drive shaft 2.

  The control of the lift / operating angle variable mechanism 1 and the phase variable mechanism 21 is not limited to the closed loop control based on the detection of the sensors 14 and 16, but may be simply the open loop control according to the operating conditions. .

  In the internal combustion engine of the present invention having such a variable valve mechanism on the intake valve side, the intake air amount is controlled by variable control of the intake valve 11 without depending on the throttle valve. In a practical engine, it is preferable that a slight negative pressure exists in the intake system for recirculation of blow-by gas and the like, although not shown, instead of a throttle valve on the upstream side of the intake passage, It is desirable to provide an appropriate throttle mechanism for generating negative pressure.

  FIG. 3 schematically shows a cross section along the longitudinal direction of the control shaft 12. As described above, the control shaft 12 is formed in a hollow shape, and lubricating oil is supplied to the hollow portion 31 inside the control shaft 12 extending along the longitudinal direction of the control shaft 12. This lubricating oil lubricates the sliding portion between the control shaft 12 and the bearing means 29, and the through-hole 33e extends from the bearing means 29e closest to the lift / operation angle control actuator 13 in the longitudinal direction of the control shaft 12. It is supplied in the hollow part 31 via.

  Here, the through hole 33 is formed so as to open to the outer peripheral surface of the control shaft 12 corresponding to the position where the bearing means 29 is disposed, and the through hole 33 is the one farthest from the lift / operation angle control actuator 13. It is set as the through-hole 33a, and it is set as the through-hole 33b, 33c, ... 33e in the order which approaches the actuator 13 for lift and operating angle control. The bearing means 29 is the bearing means 29a that is farthest from the lift / operating angle control actuator 13, and the bearing means 29b, 29c,. As for the cam bracket 26, the cam bracket 26a is the one farthest from the lift / operating angle control actuator 13, and the cam brackets 26b, 26c,.

  As shown in FIG. 4, an oil hole 32 is formed in the cam bracket 26e that constitutes the bearing means 29e. The oil hole 32 communicates with a main gallery (not shown) provided inside the internal combustion engine, and the lubricating oil ejected from the oil hole 32 causes a sliding portion between the bearing means 29 e and the control shaft 12. While being lubricated, the oil is supplied into the hollow portion 31 through a through hole 33e formed in the control shaft 12. And the lubricating oil in the hollow part 31 is supplied to the sliding part of the bearing means 29a-29d and the control shaft 12 through the through holes 33a-33d. That is, the lubricating oil is supplied into the hollow portion 31 or the lubricating oil is supplied from the hollow portion 31 to the bearing through the through holes 33a to 33e.

  In the bearing means 29a to 29d to which the lubricating oil is supplied from the hollow portion 31, the above-described oil holes 32 in FIG. 4 are not formed in the cam brackets 33a to 33d.

  In such a first embodiment of the present invention, a relatively high temperature (a large supply heat capacity) lubricating oil is supplied to the end of the hollow portion 31 on the lift / operation angle control actuator 13 side. Therefore, the temperature non-uniformity of the control shaft 12 in the longitudinal direction of the control shaft can be reduced.

  The operational effects of the first embodiment of the present invention will be described in detail using a comparative example shown in FIG. In this comparative example, lubricating oil is supplied to the hollow portion 31 from the bearing means 29b, and the sliding portions between the bearing means 29a, 29c to 29e and the control shaft 12 are lubricated using the lubricating oil in the hollow portion 31. Since it is the same structure as 1st Embodiment mentioned above except the point which exists, the code | symbol same as 1st Embodiment is attached | subjected and the overlapping description is abbreviate | omitted.

  In this comparative example, the inventors measured the temperature distribution generated in the longitudinal direction of the control shaft 12 from immediately after the start of the internal combustion engine to the end of warm-up using a strand thermocouple. Actually, since the control shaft 12 rotates during operation of the internal combustion engine, the surface temperature of each of the cam brackets 26a to 26e (see FIG. 1 described above) was measured.

  The measurement result of the surface temperature of each cam bracket 26a-26e in a comparative example is shown in FIG. Here, the characteristic line A in FIG. 6 is the surface temperature of the cam bracket 26a, the characteristic line B is the surface temperature of the cam bracket 26b, the characteristic line C is the surface temperature of the cam bracket 26c, and the characteristic line D is the surface temperature of the cam bracket 26d. The characteristic line E indicates the surface temperature of the cam bracket 26e.

  As is apparent from FIG. 6, during the warm air, the temperature of the cam bracket 26 b of the bearing means 29 b for supplying the lubricating oil to the hollow portion 31 is the highest, and the bearing closest to the lift / operating angle control actuator 13. The temperature of the cam bracket 26e of the means 29e is the lowest. In other words, transiently, the temperature of the cam bracket 26b is the highest, and the temperature of the lubricating oil decreases as the lubricating oil flows along the longitudinal direction of the control shaft 12. Therefore, the temperature of the cam bracket 26e farthest from the cam bracket 26b. Is the lowest. On the other hand, when a sufficient amount of time has elapsed, a sufficient amount of heat is brought in by the lubricating oil, so that the temperature difference between the two in the longitudinal direction of the control shaft 12 becomes small.

  However, what should be noted in FIG. 6 is that the temperature of the cam bracket 26e is significantly lower than that of the cam brackets 26a, 26c, and 26d. This is because the cam bracket 26e is not only farthest away from the cam bracket 26b, but is also strongly influenced by the lift / operating angle control actuator 13 having a relatively large heat capacity.

  Therefore, in the first embodiment of the present invention, in order to suppress the influence of the heat capacity of the lift / operating angle control actuator 13 and to reduce the temperature non-uniformity occurring in the longitudinal direction of the control shaft 12, By supplying lubricating oil from the cam bracket 26e of the bearing means 29e closest to the lift / working angle control actuator 13 to the hollow portion 31 in the control shaft 12, the lift / working angle control actuator 13 is attached to the heat capacity. Is warmed from one end side of the control shaft, which is relatively large.

  Therefore, in the first embodiment of the present invention, as shown in FIG. 7, the temperature of the cam bracket 26e during warm-up can be relatively increased, and the temperature difference from the cam bracket 26b can be reduced. That is, the control shaft 12 according to the first embodiment of the present invention can suppress the temperature distribution in the longitudinal direction from becoming non-uniform, and can reduce the occurrence of non-uniform thermal expansion in the same direction. . Therefore, in the first embodiment, the variation in the lift amount of the intake valve between the cylinders is reduced, and the occurrence of variation in the torque generated by the internal combustion engine can be suppressed.

  In FIG. 7, the characteristic line A is the surface temperature of the cam bracket 26b in the comparative example, the characteristic line B is the surface temperature of the cam bracket 26e in the comparative example, and the characteristic line C is the cam bracket in the first embodiment. The surface temperature 26b and the characteristic line D indicate the surface temperature of the cam bracket 26d in the first embodiment. Moreover, the temperature measurement of the cam brackets 26b and 26e in the first embodiment shown in FIG. 7 is performed using a thermocouple of a strand.

  In the first embodiment, the lubricating oil is supplied from the cam bracket 26e closest to the lift / operating angle control actuator 13 to the hollow portion 31 of the control shaft 12. However, in the longitudinal direction of the control shaft 12, as shown in FIG. Accordingly, the lubricating oil is supplied to the hollow portion 31 of the control shaft 12 from the cam bracket 26d which is relatively on the lift / operating angle control actuator 13 side, and the bearing means 29a to 29c and 29e are supplied by the lubricating oil in the hollow portion 31. You may make it supply lubricating oil to a sliding part with the control shaft 12. FIG.

  Also, an oil hole 32 is provided in the cam bracket 26 of the plurality of bearing means 29 so that a relatively large amount of lubricating oil is supplied to one end side of the control shaft 12 that is on the lift / operating angle control actuator 13 side. Even if lubricating oil is supplied from the plurality of bearing means 29 to the hollow portion 31 of the control shaft 12, a relatively large amount of lubricating oil is applied to the lift / operation angle control actuator 13 side where the heat capacity becomes relatively large. Since the supplied heat amount is brought in, it is possible to suppress the temperature distribution in the longitudinal direction of the control shaft 12 from becoming non-uniform. In this case, in the bearing means 29 on the lift / operating angle control actuator 13 side where a large amount of lubricating oil is desired to be supplied, the diameter of the oil hole 32 formed in the cam bracket 26 is relatively increased, or the cam bracket For example, the number of oil holes 32 formed in 26 may be relatively increased.

  Hereinafter, other embodiments of the present invention will be described. In addition, about the part of the same structure as 1st Embodiment mentioned above, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  Next, a second embodiment of the present invention will be described. In the second embodiment, in addition to the configuration of the first embodiment described above, as shown in FIG. 8, a lubricating oil supply pipe 40 as a lubricating oil supply means is connected to the control shaft 12 from the outer peripheral side of the control shaft 12. Then, the lubricating oil is supplied to the bearing means 29a to 29e by spraying or dripping the lubricating oil.

  That is, the lubricating oil is supplied from the bearing means 29e closest to the lift / operating angle control actuator 13 to the hollow portion 31 in the control shaft 12, and from the outer peripheral side of the control shaft 12 by the lubricating oil supply pipe 40. The lubricating oil is sprayed or dripped onto the control shaft 12.

  The lubricating oil supply pipe 41 communicates with an oil passage (not shown) inside the internal combustion engine, and has five openings (not shown) respectively corresponding to the five bearing means 29a to 29e. ing. Each of the openings is positioned above the corresponding bearing means 29 and is configured to spray or drop substantially the same amount of lubricating oil toward the corresponding bearing means 29.

  In such a second embodiment, the temperature of the lubricating oil supplied from the lubricating oil supply pipe 41 by spraying or dripping is not affected by the lift / working angle control actuator 13, and therefore the lift / working angle control actuator The temperature of the bearing means 29e on the 13th side can be further raised relatively, and as a result, the temperature non-uniformity in the longitudinal direction of the control shaft 12 can be further reduced. Therefore, the variation in the lift amount of the intake valve between the cylinders is reduced, and the occurrence of variation in the torque generated by the internal combustion engine can be suppressed.

  Next, a third embodiment of the present invention will be described. In the third embodiment, the amount of lubricating oil sprayed or dripped from the lubricating oil supply pipe 41 is set to the position of the bearing means 29 for supplying the lubricating oil into the control shaft 12, that is, the oil hole 32 shown in FIG. It is changed appropriately according to the position of the cam bracket 26 having.

  That is, for structural and design reasons, the bearing means 29 having the oil hole 32 must be provided at a position deviated from the substantial center in the longitudinal direction of the control shaft 12 toward the lift / operation angle control actuator 13 side. The flow rate of the lubricating oil from the lubricating oil supply pipe 40 is relatively small on the lift / operating angle control actuator 13 side and relatively large on the other side. With such a configuration, it is possible to further reduce the temperature non-uniformity that occurs in the longitudinal direction of the control shaft 12, and to reduce the variation in the lift amount of the intake valve between the cylinders. It is possible to suppress the occurrence of variation in the torque generated.

  Further, the bearing means 29 having the oil hole 32 is located at a position deviated from the substantially center in the longitudinal direction of the control shaft 12 to the side where the lift / operation angle control actuator 13 is not attached, that is, to the other end side of the control shaft 12. When it is necessary to provide the flow rate of the lubricating oil supplied from the lubricating oil supply pipe 40 to the control shaft 12, the flow rate of the lubricating oil is relatively large on one end side of the control shaft 12 and relatively small on the other end side of the control shaft 12. do it.

  Here, in the third embodiment, as a specific method of changing the flow rate of the lubricating oil from the lubricating oil supply pipe 40 in the longitudinal direction of the control shaft 12, for example, as shown in FIG. There is a method in which the diameters of the openings 42 of the tube 40 are not the same as each other, but are increased or decreased according to the corresponding bearing means 29. Alternatively, a lubricating oil supply pipe 45 may be formed as shown in FIG.

  The lubricating oil supply pipe 40 shown in FIG. 9 is formed so that the opening 42 located on the right side in FIG. 9 has a larger diameter, and the oil amount of the lubricating oil sprayed or dropped on the opening 42 located on the right side in FIG. Is increasing.

  A lubricating oil supply pipe 45 shown in FIG. 10 is obtained by branching a plurality of branch pipes 47 corresponding to the bearing means 29 from a base end portion 46 communicating with an oil passage (not shown) inside the internal combustion engine. The diameter (inner diameter) of each branch pipe 47 is large or small depending on the corresponding bearing means 29, and the diameter (inner diameter) of the branch pipe 47 located on the right side in FIG. The branch pipe 47 located on the right side in FIG. 10 has a larger amount of lubricating oil sprayed or dropped.

  Incidentally, as in the second and third embodiments described above, the lubricating oil is supplied to the hollow portion 31 in the control shaft 12, and the control oil is supplied from the outer peripheral side of the control shaft 12 to the control shaft 12 by the lubricating oil supply means. In the configuration in which the lubricating oil is sprayed or dripped, the combination of the supply position of the lubricating oil to the hollow portion 31 and the supply amount of the lubricating oil along the longitudinal direction of the control shaft 12 by the lubricating oil supply means is lifted / actuated. Depending on the heat capacity of the angle control actuator 13, a combination other than the second embodiment and the third embodiment described above may be used.

  That is, in each of the above-described embodiments, the temperature of the control shaft 12 is made substantially uniform along the longitudinal direction by using lubricating oil for the bearing means 29 that rotatably supports the control shaft 12. For example, when the heat capacity of the lift / operation angle control actuator 13 attached to one end of the control shaft 12 is very large, the hollow portion 31 is lubricated from one end of the control shaft 12. Even if the oil is supplied and the supply amount of the lubricant oil to one end side of the control shaft 12 by the lubricant oil supply means is larger than the supply amount of the lubricant oil to the other end side of the control shaft 12. The intended purpose can be achieved.

  When the heat capacity of the lift / operating angle control actuator 13 is relatively small, the lubricating oil is supplied to the hollow portion 31 from substantially the center in the longitudinal direction of the control shaft 12 and is supplied to the control shaft 12 by the lubricating oil supply means. The desired object can be achieved even if the supply amount of the lubricating oil is made substantially uniform along the longitudinal direction of the control shaft.

  For example, the lubricating oil is supplied to the hollow portion 31 from substantially the center in the longitudinal direction of the control shaft 12, and the supply amount of the lubricating oil to one end side of the control shaft 12 by the lubricating oil supply means is changed to the other of the control shaft 12. Even if it is configured to be larger than the supply amount of the lubricating oil to the end side, the intended purpose can be achieved depending on the heat capacity of the lift / operation angle control actuator 13.

  Further, the supply of the lubricating oil to the bearing means 29 is performed only by the lubricating oil supply means sprayed or dropped from the outer peripheral side of the control shaft 12 toward the control shaft 12, and the control shaft is driven by the lubricating oil from the lubricating oil supply means. It is also possible to configure so that the temperature is substantially uniform along the longitudinal direction. In this case, since lubricating oil is not supplied from the bearing means 29 to the hollow portion 31 in the control shaft 12, it is not necessary to form the control shaft 12 solid (not hollow).

  The technical idea of the present invention that can be grasped from the above embodiment will be listed together with the effects thereof.

  (1) A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A lift / operating angle variable mechanism capable of controlling expansion and contraction, an actuator attached to one end in the longitudinal direction of the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, A plurality of bearing means is provided with lubricating oil, and an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state. In the variable valve mechanism, the control shaft is formed in a hollow shape, and through one end side bearing means for supporting one end side of the control shaft among the plurality of bearing means in a hollow portion inside the control shaft extending along the longitudinal direction of the control shaft. Lubricating oil is supplied. As a result, the temperature non-uniformity of the control shaft in the longitudinal direction of the control shaft can be reduced, so that a non-uniform temperature distribution occurs in the longitudinal direction of the control shaft, resulting in non-uniform thermal expansion in the same direction. That can be reduced. Therefore, the variation in the lift amount of the intake valve between the cylinders is reduced, and the occurrence of variation in the torque generated by the internal combustion engine can be suppressed.

  (2) A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristic of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A lift / operating angle variable mechanism capable of controlling expansion and contraction, an actuator attached to one end in the longitudinal direction of the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, A plurality of bearing means is provided with lubricating oil, and an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state. In the variable valve mechanism, the control shaft is formed in a hollow shape, and lubricating oil is supplied to the hollow portion inside the control shaft extending along the longitudinal direction of the control shaft from a plurality of locations in the longitudinal direction of the control shaft, and the inside of the hollow portion Amount of lubricating oil supplied is set to be much closer to one end of the control shaft. Even in such a configuration, it is possible to obtain substantially the same effect as the variable valve mechanism for the internal combustion engine described in (1) above.

  (3) A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A lift / operating angle variable mechanism capable of controlling expansion and contraction, an actuator attached to one end in the longitudinal direction of the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, A plurality of bearing means is provided with lubricating oil, and an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state. The variable valve mechanism has a lubricating oil supply means for supplying the lubricating oil to the plurality of bearing means by spraying or dripping the lubricating oil from the outer peripheral side of the control shaft to the control shaft. It is set to spraying or dripping the relatively more lubricant as one end of the control shaft. Even in such a configuration, it is possible to obtain substantially the same effect as the variable valve mechanism for the internal combustion engine described in (1) above.

  (4) A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. And a variable lift / operating angle mechanism that can be controlled to expand and contract and a plurality of bearing means for rotatably supporting the control shaft, and the plurality of bearing means are supplied with lubricating oil and operated in the engine. In a variable valve mechanism of an internal combustion engine that can control the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the state, the lubricating oil supplied to the plurality of bearing means is The temperature in the longitudinal direction is set to be substantially uniform. Even in such a configuration, it is possible to obtain substantially the same effect as the variable valve mechanism for the internal combustion engine described in (1) above.

  (5) In the configuration described in the above (3) or (4), the control shaft is formed in a hollow shape, and control is performed via a central bearing means that supports the approximate center in the longitudinal direction of the control shaft among the plurality of bearing means. Lubricating oil is supplied to a hollow portion inside the control shaft extending along the longitudinal direction of the shaft.

  (6) In the configuration described in any one of (1), (2), (4), and (5) above, a plurality of lubricant oils are sprayed or dropped on the control shaft from the outer peripheral side of the control shaft. Lubricating oil supplying means for supplying lubricating oil to the bearing means is provided, and the lubricating oil supplying means is set to spray or drop the lubricating oil substantially uniformly along the longitudinal direction of the control shaft.

  (7) In the configuration described in (4) above, there is provided a lubricating oil supply means for supplying the lubricating oil to the plurality of bearing means by spraying or dropping the lubricating oil on the control shaft from the outer peripheral side of the control shaft. An actuator for rotating the control shaft is attached to one end in the longitudinal direction of the control shaft, and the control shaft is formed in a hollow shape, and lubricates a hollow portion inside the control shaft extending along the longitudinal direction of the control shaft. Oil is being supplied.

  (8) More specifically, the configuration according to any one of (1), (2), (5), and (7) described above is the outer peripheral surface of the control shaft corresponding to the arrangement positions of the plurality of bearing means. Are formed so that through holes communicating with the hollow portions are opened, and the lubricating oil is supplied into the hollow portions or supplied from the hollow portions to the bearing means through the through holes.

  (9) More specifically, in the configuration described in any one of (3), (6), and (7) above, the lubricating oil supply means corresponds to the arrangement positions of the plurality of bearing means and the control shaft The lubricating oil is set to be sprayed or dripped from the outer peripheral side.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which shows the whole structure of the system in 1st Embodiment of this invention. Explanatory drawing which shows schematic structure of a variable valve mechanism. Explanatory drawing which shows typically the cross section along the longitudinal direction of the control axis | shaft of the lift and working angle variable mechanism in 1st Embodiment of this invention. The top view of the cam bracket of the bearing means which supplies lubricating oil to the hollow part in a control shaft in 1st Embodiment of this invention. Explanatory drawing which shows typically the cross section along the longitudinal direction of the control axis | shaft of the lift and working angle variable mechanism in a comparative example. The characteristic line figure which shows the temperature measurement result of each cam bracket from the start of an internal combustion engine to the completion | finish of warm-up in a comparative example. The characteristic diagram which shows the temperature measurement result of each cam bracket from the start of the internal combustion engine in 1st Embodiment of this invention to the completion | finish of warm-up. Explanatory drawing which shows the whole structure of the system in 2nd Embodiment of this invention. Explanatory drawing which shows the specific structural example of the lubricating oil supply means in 3rd Embodiment of this invention. Explanatory drawing which shows the specific structural example of the lubricating oil supply means in 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Control shaft 13 ... Actuator for lift / operating angle control 26 ... Cam bracket 27 ... Cam bracket cap 29 ... Bearing means 31 ... Hollow part 32 ... Oil hole 33 ... Through hole

Claims (9)

A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A variable lift / operating angle mechanism capable of reduction control, an actuator attached to one end in the longitudinal direction of the control shaft, and rotating the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, Lubricating oil is supplied to a plurality of bearing means, and a variable valve mechanism for an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state In
The control shaft is formed in a hollow shape, and lubricating oil is supplied to the hollow portion inside the control shaft extending along the longitudinal direction of the control shaft via one end side bearing means for supporting one end side of the control shaft among the plurality of bearing means. What is claimed is: 1. A variable valve mechanism for an internal combustion engine. A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A variable lift / operating angle mechanism capable of reduction control, an actuator attached to one end in the longitudinal direction of the control shaft, and rotating the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, Lubricating oil is supplied to a plurality of bearing means, and a variable valve mechanism for an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state In
The control shaft is formed in a hollow shape, and lubricating oil is supplied from a plurality of locations in the longitudinal direction of the control shaft to the hollow portion inside the control shaft extending along the longitudinal direction of the control shaft, and lubrication supplied into the hollow portion A variable valve mechanism for an internal combustion engine, characterized in that the amount of oil is set so as to increase toward the one end side of the control shaft. A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. A variable lift / operating angle mechanism capable of reduction control, an actuator attached to one end in the longitudinal direction of the control shaft, and rotating the control shaft, and a plurality of bearing means for rotatably supporting the control shaft, Lubricating oil is supplied to a plurality of bearing means, and a variable valve mechanism for an internal combustion engine capable of controlling the intake air amount to the internal combustion engine by changing the lift and operating angle of the intake valve according to the engine operating state In
Lubricating oil supply means for supplying lubricating oil to a plurality of bearing means by spraying or dripping the lubricating oil from the outer peripheral side of the control shaft to the control shaft is provided. A variable valve mechanism for an internal combustion engine, which is set to spray or drip a relatively large amount of lubricating oil. A variable valve mechanism for an internal combustion engine capable of continuously changing the valve lift characteristics of the intake valve, and continuously increasing the lift and operating angle of the intake valve by rotating a control shaft extending along the cylinder row direction. , A reduction / controllable lift / operating angle variable mechanism, and a plurality of bearing means for rotatably supporting the control shaft. The plurality of bearing means are supplied with lubricating oil and are adapted to engine operating conditions. In the variable valve mechanism of the internal combustion engine that can control the intake amount to the internal combustion engine by changing the lift and operating angle of the intake valve,
A variable valve mechanism for an internal combustion engine, wherein the lubricating oil supplied to the plurality of bearing means is set so that the temperature in the longitudinal direction of the control shaft is substantially uniform.   The control shaft is formed in a hollow shape, and a lubricating oil is provided in a hollow portion inside the control shaft that extends along the longitudinal direction of the control shaft via a central bearing means that supports the approximate center of the longitudinal direction of the control shaft among the plurality of bearing means. The variable valve mechanism for an internal combustion engine according to claim 3 or 4, characterized in that is supplied.   Lubricating oil supply means for supplying lubricating oil to a plurality of bearing means by spraying or dropping lubricating oil from the outer peripheral side of the control shaft to the control shaft is provided. 6. The variable valve mechanism for an internal combustion engine according to claim 1, wherein the lubricating oil is set to be sprayed or dripped substantially uniformly along the line.   Lubricating oil supply means for supplying lubricating oil to a plurality of bearing means by spraying or dripping the lubricating oil from the outer peripheral side of the control shaft to the control shaft is provided, and at one end in the longitudinal direction of the control shaft, the control shaft The control shaft is formed in a hollow shape, and lubricating oil is supplied to a hollow portion inside the control shaft that extends along the longitudinal direction of the control shaft. 5. A variable valve mechanism for an internal combustion engine according to 4.   A through hole communicating with the hollow portion is formed on the outer peripheral surface of the control shaft corresponding to the arrangement position of the plurality of bearing means, and the supply of lubricating oil into the hollow portion or the inside of the hollow portion through these through holes is formed. The variable valve mechanism for an internal combustion engine according to any one of claims 1, 2, 5, and 7, wherein the lubricating oil is supplied from said to the bearing means.   The lubricating oil supply means is set so as to spray or drip the lubricating oil from the outer peripheral side of the control shaft in correspondence with the arrangement positions of the plurality of bearing means. A variable valve mechanism for an internal combustion engine according to any one of the above.

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